weird temp issue

[91kid]

Ok so i was driving the cb to work yesturday, it was 38* out and i had the heater cranked

the heat kept getting warm and then cooling off
the temp gauge indicated that the engine was doing the same thing..

over the course of my 45 minute drive the car never reached operating temp, it kept going up about 1/4 of the way then back to cold, then back to 1/4, and repeat

on my way home, temp was 65-70 and the car went right to the middle of the guage after about 5 mins of driving and stayed up the whole way home

it idles and runs fine, other then wanting to idle at stop lights at 1500rpm which is normal for a cold car lol

any help?
thermostat maybe?

[evil_demon_01]

First thing I'd check the coolant level, then replace the thermostat.
They are cheap and easy enough to do for peace of mind.

[91kid]

radiator is full, and the overflow bottle is up to its line..

one other addition while sitting at my coffee place waiting for coffee that morning the car seemed to get closer to operating temp then when i was moving, its almost like the cooling system is working TOO well lol